In
computer science, applied programming techniques are depending on
the focus on the goals, and programming an emulator is an example
of this.

According
to information on the Mednafen
site, now 100% support gpl Sega (genesis and megadrive) emulation
is complete, given the amazing feat in just 6 months of
reimplementing the processors codes motorolla
68000 , Zilog
Z80 and the PSX / PSXG (GPU) R3000

This
is the main reason why the Mednafen is slower, although his first
goal was to be 100% GPL, functionality and performance have
sacrificed for it, two conflicting goals but commendable efforts
should be recognized. For fans of the obtuse free software GPL
movement, the work on CPU cores and the sound module was
rewritten

This
is good news for the GPL zealots, allows play sega megadrive and
finally using a free software emulator, but it is illogical
because when you use a rom are violating laws, due dump it the rom
are not legal (event if you own a rom, but this only meets the
overcome the patent is not still valid).

As
a programmer respect: it shows two things about this project
(Mednafen), its developers are the mostes, real mayor league
programmers. Rewriting the code on the hard about motorolla
68000 is quite a feat, especially for its
communication near the Zilog
Z80 used for sound with most assembler
code into C code.

Mednafen
implements ported source code from famous Gens/Gens32 or GX, which
uses the powerful library/emulator Starscream
680x0 for motorolla processors
680000, too optimized and very difficult to rewrite, in addition
to its proximity and collaboration with the assembly code of the
SH2 famous; also using RAZE
Z80 code (ZilogZ80 ) for
emulate sound. Few people know that I speak because it is pure
machine architecture and assembly code where a bit silly is
not supported object orient programming, neither reimplementation
of code, this is not good here, because the REAL speed
is everything! No apparent speed that makes us believe google at
gmail loading! PFFFF The prowess of this team is rewriting
the code with minimal impact on performance.

In
addition to this there are two things that stand out more,
reimplementation of core R3000 PSX and SNES emulation.

About
PSX's R3000's emulation there's not much to say, best not speak,
can be spoiled the great work on the sega M 68000. With said that
requeriments for emulate a PSX are 4 cores CPU!, how stupid god!!
who comes that! Better and cheaper to buy and import a real PSX
console and replace the damaged lens from empire country (EEUU)!!
More info about R3000 MIPS CPU's and firts procesors here:
http://www.cpu-world.com/CPUs/R3000/index.html

Contrary
to what any think, the SNES code is not taken from excelent snes9x
(which implements a lot of assembler code to optimize their large
effects and features).

The
code for Mednafen SNES was taken from a lazy and stupid project,
slow and windoser: bsnes byuu
code, god! so bad right decision! As a result, emulation is
VERY SLOW, excessive resource consumption, focused on "beauty"
code instead of speed and efficiency of performance. Developers
believe that "efficient" is to reuse code, no sir,
efficiency meas that it works efficiently and fast way possible.
bsnes is the worst SNES emulator, and the only useful in it its
organization of code, sure netter say safe that is best, so
best that nobody used this emulator, event hav well implemented
code.